1. Field of the Invention
This invention is about a procedure to localize and identify anomalies of a medium like the ones found during seismic campaigns.
2. Description of the Related Art
The image of a seismic area is generally shown as one or many two-dimensional seismic section, referred to as seismic 2D, defined by axis x and t, or by three-dimensional seismic sections, referred to as seismic 3D, defined by axis x, y and t or z, where t is time and z is depth.
In a seismic block, a seismic event is found partly by one or many shot points and from the receivers associated with the shot point, defined by their coordinates at axis x and y, and partly by the time t it takes to go from the shot point to the corresponding receiver or the depth z where it is located.
An anomaly is viewed by interpreters as a seismic event. The study of anomalies in a medium allows for better understanding of the medium, as some anomalies can be clues on the presence or absence of hydrocarbons (water and oil) in the given medium.
The detection of anomalies on a seismic section comprised of a large number of seismic traces previously assembled within given criteria as for example in common middle points (CMP), at a common receiver, etc . . . is done manually by the interpreter. Subsequently, the selection or rejection of an anomaly depends solely on the judgment of the interpreter and his ability to interpret the seismic section correctly. FIG. 1 represents a seismic section (x, t) on which anomalies, A1 and B1 for example, are platted by the interpreter. The plotted anomalies can be considered as either different, identical or of the same nature. As can be seen in FIG. 1, to the left and in the second lower half, many anomalies Al that overlap can be found, making it difficult to determine their nature. In the presence of a fault in a medium, it is often faced two anomalies which are unrelated. These two anomalies are on different levels and can be viewed as the same from one end to the other of the fault while the interpreter views each as divided and delimited by the fault without being able to clear the ambiguity.
In any case, the manual detection of an anomaly cannot take into account all anomalies especially those that are barely visible or that are hidden by other anomalies.